The brutal blitzkrieg: the 1939 invasion of Poland

When the Jews arrived, they saw a Wehrmacht truck, on which the canvas cover was drawn back to reveal a heavy machine gun. Burst after burst of gunfire rang out, sweeping back and forth until the men stopped writhing. Then the soldiers departed and the process began again. In all, over three days, some 600 of Przemyśl’s Jews would be murdered. It was, according to one eyewitness, “like a scene from Dante’s hell”.

• Listen | Roger Moorhouse delivers a lecture on the German invasion of Poland in 1939

The German invasion of Poland, which began on 1 September 1939, opened the Second World War in Europe, yet it nonetheless remains a subject mired in misunderstanding. Aside from the hoary old myths of the feckless Poles sending their cavalrymen to engage German armour, little else seems to have penetrated the popular narrative.

One way of rectifying such a lack of knowledge might be to point out the remarkable brutality that was meted out to the Polish population during the campaign. Of course, actions against Europe’s Jews, like that at Przemyśl, were grimly commonplace during the war. But readers might be surprised to learn that the victims in 1939 were not only Polish Jews, and the perpetrators were not only the Germans; Soviet forces, too, contributed their part to the murderous climate.

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Dehumanised stereotype

Anti-Semitism was clearly the driver behind some German atrocities. For many German soldiers, Poland represented their first exposure to Jewish populations that appeared to approximate to the dehumanised stereotype presented by Nazi propaganda. Their response was predictably brutal. At Końskie, German troops fired into a crowd of Jews who had been rounded up to dig graves, killing 22. At Błonie, west of Warsaw, 50 Jews were massacred; at Pułtusk a further 80. There are numerous other examples.

But, all Poles – whether Jewish or not – were under threat in 1939. Executions of PoWs were not uncommon. At Ciepielów, 300 Polish prisoners were machine-gunned after a brief engagement halted the progress of the German 15th Motorised Infantry Regiment. Perhaps the worst example occurred at Śladów, where 358 Poles – soldiers and civilians – were massacred on the banks of the river Vistula, following the failure of the Polish counter-attack on the river Bzura.

Inevitably, however, it was civilians who bore the brunt of the killing. In one example, 12 ‘partisans’ were executed in revenge for the killing of a German officer: the youngest was aged 10. In Wyszanów, 17 women and children were killed when grenades were thrown into a cellar, despite the victims’ pleas for mercy. Farmers were particularly at risk, given that they often possessed some sort of weapon and could thus easily be labelled as partisans. Eighteen were murdered after the defence of Uniejów, for example; a further 24 were executed at Wylazłow.

Seventy-two Poles were massacred by the Germans in response to the death of two horses in a friendly fire incident

In truth, any pretext sufficed. Forty Poles were massacred at Szymankowo after a German surprise attack was thwarted; another 50 were killed at Sulejówek in retaliation for the death of a single German officer. In one shocking example, 72 Poles were massacred by the Germans at Kajetanowice in response to the death of two horses in a friendly fire incident.

There were many drivers of this brutalisation. Contemporary German accounts bemoaned the inexperience of German soldiers, whose “nervousness and anxiety” had resulted in so many shootings and wanton destruction.

The nature of the warfare must also have contributed. Though Blitzkrieg was not yet German military doctrine, the campaign in Poland was often marked by swift advances that disrupted a more static Polish defence, thereby causing many defenders to be left behind the line, where continued resistance could easily be interpreted as the work of bandits and irregulars.

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There may also have been a pharmacological explanation for the brutal treatment of prisoners. ‘Pervitin’, a tablet form of methamphetamine, which produced improvements in energy, alertness and self-confidence, was increasingly popular among German soldiers at that time. The military benefits are obvious, but there can also be little doubt that – by lowering inhibitions – the drug also made soldiers more likely to commit atrocities.

Yet, valid though they may be, such explanations can only ever give a fraction of the story. In this regard, a comparison with the French campaign of the following summer is instructive. There, German troops were still comparatively inexperienced, Pervitin was still widely available, and Blitzkrieg was arguably used to greater effect. But there were far fewer atrocities. The 46 days of the French campaign saw around 25 massacres of PoWs and civilians, including those at Le Paradis, Wormhoudt and Vinkt.

• Read more: Did the Versailles peace treaty trigger another world war?

In the 36 days of the September campaign, by comparison, there were more than 600 massacres carried out by the Germans alone; an average of over 16 per day. Even allowing for embellishment, the disparity is astonishing, and surely points to a more fundamental factor driving German behaviour.

Clues are abundant in the letters and diaries of German soldiers, many of whom described the Poles as “uncivilised”, “filthy”, “a rabble”; in short, as one soldier confessed, barely human. Such attitudes, though catalysed and radicalised by Nazi propaganda, were nothing new, but crucially the war gave the green light to their violent expression. And if the enemy was perceived in this manner, it was easy for conventional morals and behaviours to be suspended. As one soldier wrote: “The Poles behave in an unhuman way. Who can blame us for using harsher methods?” It was a neat euphemism for racially motivated murder.

A belligerent liberation

While the Germans imported race war to western Poland, the Soviets brought class war to the east. The Kremlin had sold its invasion of eastern Poland – carried out on 17 September in line with the Nazi-Soviet Pact – as a “liberation”, but it was decidedly belligerent, with half a million combat troops and nearly 5,000 tanks confronting the lightly armed forces of the Polish border protection corps.

For those Poles who fell under Soviet control, there was no doubt about the Red Army’s revolutionary intentions. In countless towns and villages, Soviet officers goaded the masses to rise up against their “lords and oppressors”, to seize property and “avenge the pain of exploitation with blood”.

The murder of 22,000 Polish officers demonstrated that the Soviets aimed at wholesale social revolution

Local communist militias quickly complied, targeting landowners and local officials. Victims were simply dragged from their beds and lynched, or beaten to death. One court official was tied by his feet to a horse and cart, which was then driven around the cobbled streets until he was dead.

Prisoners of war were also sorted according to their social class. Officers were routinely separated from other ranks for interrogation, along with those who were especially well dressed, or well equipped. In time, with so many escaping the net by shedding their uniforms or pulling off their rank insignia, the Soviets began checking their prisoners' hands. Beloruchki – those with white, uncalloused palms – were clearly not from the working class, and so were also detained.

Many of them were then taken to prisons where they would be stripped of everything they had – watches, razors, belts – before being packed into cattle cars for the long journey eastward to an unknown fate. For some, at least, it was a journey that would end in the death pits of Katyń forest.

In some cases, Soviet class fury would be assuaged more immediately. Like the Germans, the Red Army was content – in the name of ideology – to forego the moral norms of warfare. A group of injured Polish prisoners taken near Wytyczno, for instance, was locked in the town hall and denied medical assistance. By the time help arrived the following day, all of them had bled to death.

Officers were often simply taken to one side and executed. When Polish prisoners heard a volley of gunfire after their surrender at Mokrany, one of them asked his Red Army escort whether fighting was still going on. He was told: “Those are your masters, shot dead in Mokrany forest.”

One of those similarly dispatched was the commander of the Polish garrison at Grodno, General Józef Olszyna-Wilczyński, who was captured by Soviet soldiers on 22 September. Taken to one side, along with his adjutant, he was executed, and his bloodstained effects were handed to his wife, who had been travelling with him. Inspecting his body, she recalled: “He was still warm, but there was no life left in him.”

The true scale of Soviet persecution of Polish prisoners and civilians is unknown; the Kremlin’s propaganda and its rigid control of the media and of memory meant that many accounts would have died with the surviving witnesses, in Polish prisons, or in the gulags of Siberia.

Yet, the political intention – and the scale of the ambition behind it – can be gauged by the Katyń massacres of the following year. The murder of 22,000 Polish officers taken prisoner during the September campaign – executed by their Soviet captors – demonstrated that the Soviets aimed at nothing less than a social revolution.

Those victims, like Olszyna-Wilczyński before them, represented the Polish elite: army officers, doctors, lawyers, intellectuals, indeed all those who were seen as the best able to foster and coordinate resistance against Soviet rule. Their wholesale elimination was – to the gentlemen of the Kremlin – an essential precondition for the successful communisation of Polish society. Murder, then, was not carried out in a haphazard manner, or in the heat of battle. It was an ideologically driven necessity.

Barbarism backdated

It is often suggested that the true barbarisation of warfare in the Second World War began with the German invasion of the Soviet Union in June 1941, when German death squads inflicted their murderous racial ideology on the helpless populations of Ukraine and Belarus. There is something to be said for that argument, of course, not least because German military domination was then at its highest, and that is when the Holocaust began in earnest.

Yet we should perhaps backdate the start of that barbarisation process to September 1939, to a campaign that has been routinely overlooked by historians as a sideshow, an irrelevant prelude to the momentous events that followed.

The Polish campaign was far from militarily insignificant, however. It saw the grim debut of many of the methods that would later earn dark renown: indiscriminate bombing, the deliberate targeting of civilian populations, and – most notably of all – the Blitzkrieg itself, the doctrine of movement, using armoured spearheads to prevent the creation of a coherent phased defence.

Aside from those nefarious innovations, it is perhaps the aspect of barbarisation that deserves the closest scrutiny. Barbarisation was not a consequence of the opening years of the war, a creeping radicalisation in which inhibitions were gradually shed and ideologies were allowed free rein. Rather it was there from the start, a key driver of Germany’s early military successes and an essential component of the racist ideology that underpinned the ‘New World Order’ by Adolf Hitler.

Crucially, too, the September campaign reminds us that it was not only the Germans who subscribed to a revolutionary world view; it was not only Hitler’s army that sought to advance its ideological goals at the point of its bayonets. In that respect, Stalin’s Red Army had just as much blood on its hands as the Wehrmacht.

Roger Moorhouse’s is the author of First to Fight: The Polish War 1939 (Bodley Head in September, 2019)

This article was first published in the September 2019 edition of BBC History Magazine